The present invention relates to a new and improved decorated or ornamented article, to an improved method of fabricating such decorated articles, and to the use of silicon substrates coated with silicon compounds and serving as the decorated article or for use with the decorated article.
As is well known very thin optical transparent layers in reflected light appear to the eye, owing to interference phenomena, as colored, although the layers consist of practically colorless material. Examples of such phenomena are the color effects of soap bubbles or mother-of-pearl and similar inorganic materials (opal) which are conventionally used for the fabrication of decorative or ornamental articles. There are furthermore known the so-called annealing or tempering colors which arise upon heating of iron alloys and which are predicated upon the formation of oxide layers. The thickness of such oxide layers is dependent upon the momentarily employed "annealing temperature", and which oxide layers appear to be colored ("annealing colors") when viewing the same in reflected light, without in reality being so inasmuch as the mass of the layer material is colorless.
Typical in this regard is, for instance, the cyaneous color of watch springs, i.e., the interference color of a thin layer of iron oxide which forms at annealing temperatures of 295.degree. C. upon the metallic base or matrix material and having a thickness less than 100 nanometers (nm). Such annealing colors, generally, however, do not have any decorative functions, rather are the incidental consequence of temperature treatments for obtaining certain material properties.
For the fabrication of decorative or ornamental articles there were hardly suitable the conventional annealing color layers of substrates formed of iron alloys in comparison to the conventional lacquer- or colored layers because of their comparatively high corrosion sensitivity, their relatively low mechanical strength (scratch sensitivity) and, in particular, due to the difficulties in producing reproduceable color effects.